Pseudasphondylia saohimea Matsuda, Elsayed & Tokuda, 2021

Matsuda, Hiroki, Elsayed, Ayman Khamis, Kim, Wanggyu, Yamauchi, Satoshi, Libra, Martin, Kamata, Naoto, Yukawa, Junichi & Tokuda, Makoto, 2021, A new species of Pseudasphondylia (Diptera: Cecidomyiidae) associated with Magnolia kobus DC. var. borealis Sarg. (Magnoliaceae) in Japan, Biodiversity Data Journal 9, pp. 68016-68016 : 68016

Pseudasphondylia saohimea Matsuda, Elsayed & Tokuda sp. n.

Materials

Type status: Holotype. Occurrence: sex: male; lifeStage: adult; Taxon: order: Diptera ; family: Cecidomyiidae ; genus: Pseudasphondylia ; specificEpithet: saohimea; taxonRank: species; nomenclaturalCode: ICZN; Location : country: Japan; stateProvince: Aomori; locality: Ashizaki , Mutsu City ; Event : samplingProtocol: reared from a leaf bud gall on Magnolia kobus var. borealis (Magnoliaceae) collected on 10.v.2015 by S. Yamauchi Type status: Paratype. Occurrence: individualCount: 7; sex: males; lifeStage: adult; Taxon: order: Diptera ; family: Cecidomyiidae ; genus: Pseudasphondylia ; specificEpithet: saohimea; taxonRank: species; nomenclaturalCode: ICZN; Location : country: Japan; stateProvince: Aomori; locality: Ashizaki , Mutsu City ; Event : samplingProtocol: reared from leaf bud galls on Magnolia kobus var. borealis (Magnoliaceae) collected on 10.v.2015 by S. Yamauchi Type status: Paratype. Occurrence: individualCount: 8; sex: females; lifeStage: adult; Taxon: order: Diptera ; family: Cecidomyiidae ; genus: Pseudasphondylia ; specificEpithet: saohimea; taxonRank: species; nomenclaturalCode: ICZN; Location : country: Japan; stateProvince: Aomori; locality: Ashizaki , Mutsu City ; Event : samplingProtocol: reared from leaf bud galls on Magnolia kobus var. borealis (Magnoliaceae) collected on 10.v.2015 by S. Yamauchi Type status: Paratype. Occurrence: individualCount: 3; lifeStage: mature larvae; Taxon: order: Diptera ; family: Cecidomyiidae ; genus: Pseudasphondylia ; specificEpithet: saohimea; taxonRank: species; nomenclaturalCode: ICZN; Location : country: Japan; stateProvince: Aomori; locality: Ashizaki , Mutsu City ; Event : samplingProtocol: collected on 19.v.2019 by S. Yamauchi at the type locality Type status: Paratype. Occurrence: individualCount: 4; lifeStage: pupal exuviae; Taxon: order: Diptera ; family: Cecidomyiidae ; genus: Pseudasphondylia ; specificEpithet: saohimea; nomenclaturalCode: ICZN; Location : country: Japan; stateProvince: Aomori; locality: Ashizaki , Mutsu City ; Event : samplingProtocol: reared from a leaf gall on Magnolia kobus var. borealis (Magnoliaceae) collected on 10.v.2015 by S. Yamauchi Type status: Paratype. Occurrence: individualCount: 3; sex: females; lifeStage: adult; Taxon: order: Diptera ; family: Cecidomyiidae ; genus: Pseudasphondylia ; specificEpithet: saohimea; taxonRank: species; nomenclaturalCode: ICZN; Location : country: Japan; stateProvince: Hokkaido; locality: Takaoka ( Tomakomai Experimental Forest , The Field Science Center for Northern Biosphere , Hokkaido University ), Tomakomai City ; Event : samplingProtocol: collected on 31.v.2015 by M. Libra Type status: Paratype. Occurrence: individualCount: 1; sex: male; lifeStage: adult; Taxon: order: Diptera ; family: Cecidomyiidae ; genus: Pseudasphondylia ; specificEpithet: saohimea; taxonRank: species; nomenclaturalCode: ICZN; Location : country: Japan; stateProvince: Hokkaido; locality: Takaoka ( Tomakomai Experimental Forest , The Field Science Center for Northern Biosphere , Hokkaido University ), Tomakomai City ; Event : samplingProtocol: collected on 31.v.2015 by M. Libra

Description

Head (Fig. 2 a-f). Eye bridge 6-7 facets long, facets rounded. Antenna: scape with more setae ventrally than dorsally; pedicel spheroid, with few scattered setae ventrally and dorsally; flagellomeres generally cylindrical, nodes setose and microtrichose, with appressed circumfila and short, naked necks; male flagellomeres I-II not fused, female flagellomeres I-IX becoming noticeably shorter successively, flagellomeres X-XII successively more foreshortened, flagellomere X 1.5 times as long as wide, flagellomere XI about 1.3 times as long as wide, flagellomere XII spheroid; male flagellomeres with anastomosing wavy circumfila; male flagellomere XII sometimes with tiny apical projection as in Fig. 2f. Palpus: 3-segmented, each with a few setae and scales, first segment shortest, 23-28 μm long, second about twice as long as first, third about twice as long as second.

Thorax (Fig. 2 g-i). Anepisternum with 23-26 scales; anepimeron with 17-23 setae (n = 6). Acropods: claws bent after mid-length, empodia as long as claws. Wing: length 2.5-3.2 mm (n = 4) in male and 2.9-3.6 mm (n = 4) in female; width 1.0-1.4 mm (n = 4) in male and 1.2-1.6 mm (n = 4) in female; Rs joining C posterior to wing apex.

Female abdomen (Fig. 3 a). Tergites I-VII rectangular, evenly covered with scales, with lateral setae and without anterior pair of trichoid sensilla; tergites I-VI with 1-2 posterior rows of setae, but tergite VII with 2-3 rows; tergite VIII bare. Sternites II-VII with anterior pair of trichoid sensilla situated laterally; sternites II-VI rectangular, anteriorly with scattered setae and scales, posteriorly with one row of setae usually mixed with some scales; sternite VII about two times longer than VI, covered with scattered setae and scales. Ovipositor: protrusible needle-like portion about 3.5 (3.4-3.6; n = 3) times longer than sternite VII; cerci undifferentiated.

Male abdomen (Fig. 3 b). Tergites I-VII with 2-3 posterior rows of setae, otherwise as in female. Sternites II-VII as sternites II-VI in female; sternite VIII about 0.5 times shorter than VII, covered with scattered setae and few scales. Terminalia (Fig. 3b): Gonostylus suboval, with setae dorsally and ventrally on distal two thirds, with two sclerotised teeth; cerci oval, setose; hypoproct shorter than cerci, basally wider than distally, bilobed, each lobe with one seta; gonocoxal lobes present; aedeagus tapered.

Mature larva (Fig. 4 ). Body colour in life orange. Spatula: anteriorly with four lobes, outer two longer than inner two. Three lateral papillae present on each side of midline, two with setae. Three pairs of asetose pleural papillae present anteriorly on prothorax. Two pairs of asetose pleural papillae on meso- and metathorax. One pair of setose pleural papillae on abdominal segments I-VIII. Two sternal papillae on each thoracic segment and abdominal segments I-VII, with setae, except on prothorax without setae. Two pairs of dorsal papillae present, without setae on thoracic segments and only outer pair with setae on abdominal segments I-VII; a pair of setose dorsal papillae on abdominal segment VIII. Terminal abdominal segment with two setose terminal papillae and two asetose anal papillae present.

Pupa (Fig. 5 ). Two setose and two asetose cephalic papillae on tubercles. Antennal horns greatly enlarged, tapered and dorsoventrally flattened, serrate along anterior margin. Antennal papillae absent. Lower and lateral facial papillae not visible. Prothoracic spiracle elongated, slightly curved, about 160 μm long, with tracheae extending to tip. Abdominal spiracles present on segments II-VI, each spiracle about 0.3 times as long as prothoracic spiracle. Abdominal terga I-VII with anterior pair of trichoid sensilla, 5-6 rows of spines and three pairs of setose dorsal papillae; tergum VIII with 5-6 rows of spines and two setose dorsal papillae.

Etymology

The specific name, Pseudasphondylia saohimea , is derived from “Saohime”, a Japanese goddess of spring, because blooming of the host plant Magnolia kobus var. borealis is a symbolic event announcing the beginning of spring in northern Japan. Galls of P. saohimea become conspicuous on the host also in early spring.

Distribution

Japan, Hokkaido and Honshu (Aomori Prefecture).

Biology

Pseudasphondylia saohimea is univoltine. Third instars and pupae were found in the galls in mid-May and adults emerged directly from the galls in mid- to late May. All mature galls collected in July were empty, indicating that no individuals had entered long-term diapause. In rearing conditions, adults emerged in the morning and mated around 11:00 h, suggesting that the gall midge is a diurnal species. The adults are supposed to oviposit into host buds. First instars were found in undeveloped bud galls in late September. They possibly overwinter in the undeveloped bud galls and develop to the second and third instars in the following spring.

Host plant

Magnolia kobus DC. var. borealis Sarg. ( Magnoliaceae ), “Kita-kobushi” in Japanese.

Gall

Pseudasphondylia saohimea induces hairy leaf bud galls on Magnolia kobus var. borealis ( Magnoliaceae ). The galled buds remain closed and indistinguishable in appearance from ungalled buds until the following spring and rapidly grow with bud burst. Mature galls are 2.7-6.0 mm in diameter and 5.1-13.7 mm in length (n = 45). Galls are multi-chambered and each chamber contains a single gall midge larva.

Parasitoids

The following three species of hymenopteran parasitoids were reared from the mature galls: Pseudocatolaccus sp. ( Pteromalidae ) from Hokkaido and Aomori, Torymus sp. ( Torymidae ) from Hokkaido and Eurytoma sp. ( Eurytomidae ) from Aomori.

Notes

The new species is distinguishable from most of its other congeners in Japan by the number of palpal segments: three in the new species, but two in P. neolitseae and four in P. rokuharensis , P. kiritanii and P. tominagai . Although P. matatabi and P. elaeocarpi have three-segmented palpi, they are easily distinguished from the new species by their cerci which are shorter than the hypoproct. The larval spatula of the new species has four lobes of which the outer two are longer than the inner two. However, the larval spatula of P. neolitseae has only two lobes anteriorly and the other species have four lobes of which the inner two are longer than the outer two. In the pupa, five pairs of long abdominal spiracles are present in the new species, while only three pairs are present in P. rokuharensis , P. kiritanii , P. elaeocarpi and P. tominagai and four pairs in P. matatabi . The pupa of P. neolitseae , which has five pairs of abdominal spiracles, is otherwise similar to the new species, but it can be distinguished by dorsal abdominal spines that are markedly shorter than in P. saohimea .

In the key to the males of world Pseudasphondylia species in Elsayed et al. (2019), P. saohimea will run to couplet 5 that separates P. matatabi and P. elaeocarpi . In order to update the key and include P. saohimea , couplet 5 is amended and a sub-couplet is added as in Table 1 .

Molecular phylogenetic analysis

In the ML tree (Fig. 6 ), Pseudasphondylia species constructed a monophyletic clade relatively supported by 65% bootstrap value. Although P. saohimea constructed a clade with P. rokuharensis , their bootstrap support was lower than 50%. Genetic divergence of P. saohimea and the other Japanese Pseudasphondylia species was high and ranging between 15% to 21% (15% between P. saohimea and P. rokuharensis ; 16% between P. saohimea and P. matatabi ; 17% between P. saohimea and P. tominagai and P. kiritanii ; 21% between P. saohimea and P. neolitseae ).

Figures

Figure 2. Pseudasphondylia saohimea sp. n. a. Head; b. Female flagellomere V. c. Male flagellomere V; d. General shape of female flagellomeres; e. General shape of male flagellomeres; f. Male flagellomeres X-XII; g. Wing; h. Acromere of fore-leg. i. Acromere of hind-leg. Scale bars = 50 µm.

Figure 3. Pseudasphondylia saohimea sp. n. a. Terminal part of female abdomen; b. Male terminalia. Scale bars = 50 µm.

Figure 4. Larva of P. saohimea sp. n. a-b. Shape variation in sternal spatula and associated papillae; c. Dorsal view of 8 th and terminal abdominal segments. Scale bars = 50 µm.

Figure 5. Scanning electron micrographs of pupa of Pseudasphondylia saohimea sp. n. a. Ventral view of head b. Prothoracic spiracle; c. Lateral view of abdominal segments. Scale bars = 50 µm.

Figure 6. Maximum Likelihood phylogenetic tree of Japanese Pseudasphondylia species, based on a fragment of COI. Bootstrap values are indicated for nodes that gained> 50 % support in 1,000 replications.